Variable-speed device



x.. D, DUNCAN. VARIABLE SPEED DEVICE. A

APPLICATION HLED APR. 7, 1919.

1,355,948, Patented 00A-19,192D.

/5 i s a '/fj-l JNETED STATES PATENT OFFICE.

XAvIER BQDUNCAN, or NEWBERG, OREGON.

VARIABLE-SPEED IDE-VICE.

To all whom 'it may concern:

Be itlrnown that XAVIER B. DUNCAN, a citizen of the United States,residing at Newberg, in the county of Yamhill and State of Oregon, haveinvented certain new and useful improvements in Variable-Speed Devices;and I do declarethe following to be a full, clear, and exact descriptionof the invention, such as willenable others skilled in the art to whichit appertains to malte and use the same. f Y

This invention relates to variable speed devices, and it relates moreparticularly to an improved three-speed Ygear mechanism for bicycles orother motor driven vehicles.

Another object is toprovide an improved device of this character inwhich va single securing means effects the several functions ofunitingrthe several members of the gearV casing in unison, securing thegear wheels in their respective operative positions, and supporting andguiding a shifter clutch actuating device. Qther objects and advantagesmay become apparent to persons who read the following details ofdescription in connection with the accompanying drawings in which:

Figure 1 is a central vertical section inthe plane of the axes of thedriving and driven shafts.

Fig. 2 is a vertical sectional view along the line 2-2 of Fig. 1. Y

Referring to these drawings in'detail, in which similar referencecharacters correlspond with similar parts throughout the several views,the device consists broadly of a gear casing 5. a driving shaft 6 andgear wheels carried thereby, a driven shaft t and a setfof gear wheelsthereon, a shifter 8, and

a securing means 9, the latter also serving as a support and guide forthe shifter.

The casing 5 comprises-two casing-heads 10 and 11 and a barrel 12, thelatterpr efer' ably being somewhat elliptical as 1llus,

trated. The casing-heads 10 and 11 are each provided with a flange 13which fits around the contiguous end of the barrel12', and one or moreof the bolts .or securing members k9 may be engaged with thecasing-heads as indicated in l? 1 so as to co-act with the casing-headsfor vclamping the'barrel 12v'andv thus to form the unitary gear casing5, it being understood that one or two nuts may be provided on each bolt9 so lthat the cas- Y ing may be quickly and easily takenapart by theremoval of one'of the nuts.y The Application filed April 7, 1919. SerialNo.` 287,932.

Specification of Letters Patent. Patented Oct 19, 1920.

casing-heads are provided with suitable re-` cesses forl holdingbushings or bearing elements 14, 15 and 16 in which the shafts6 and 7are journaled. However, the shaft6is not in direct contact with thebearing 15, but a 4combined bearing and transmission member 17k isjournaled in the bearing 15, and thev shaft 6 is journaled in thismember 17. The member 17 comprises a sleeve 1S, a gear wheel 19 and aclutch element 20, the outer end of the sleeve 18 being externallyscrew-threaded te receive a lock nut, and also being provided with aseat on which a sprocket wheel 21 is secured by means of the lock nut.'i y As this particular embodiment of the invention is intended for useon a pedal operated machine, the shaft 6 has cranks 22 secured thereonby appropriate means, and themid-dle portion of the shaft 6 is of largerdiameter than its end portions, so that sheulders 23 and 24 areprovided. The provision of these shoulders not only `preventslongitudinal movement of the shaft 6 in its bearings, but also preventsmovement of the transmissionmember 17, it being understood that one sideof thistransmissien member bears against the casing-head 10, while-itsother side bears against the shoulder 23, it being understood that thebushing 15 constitutes a part ofthe casinghead 10. Moreover, atransmissionvmember 25 is Vjournaled on the'shaft 6, andjone of sidesbears against the shoulder 24, while its other side bears against theelement 14 of the casing-head 11, so that axial move- I ment of themember 25 is prevented, while this member `is permitted to rotate freelyon the shaft 6. 'The member 25 comprises a a peripheral groove 32 beingformed in this member 28. The clutchelement 30 is interengageable withthe clutch element 20, and the lclutch element 31 is inter-engageablewith the clutch element 27, so that the members 17 and 25 areinterchangeably operatable by the member 28. The shifter 8 is slidablealong the bolt orrod'9 and has a bifurcated arm 8 which engages with thegroove 32, and any appropriate means may be employed for moving theshifter along the rod 9, an arm 8a being illustrated to show one meanswhereby the shifter may be actuated from an extraneous source of power,it being noted that a slot or opening 12 may bev provided for permittingthe necessarymovement of the arm 8a. Y

Within the bushings or Ybearings 16 is jouinaled the shaft 7, and a setof gears is keyed on this/shaft, keys such as indicated at 7 beingpreferably employed for this purpose, the small, medium and large gearsof this setbeing indicated by the numerals 33, 34 and 35 respectively.The outer gears 33 and 35are seated against the elements 16 of thecasing-heads, and the intermediate gear 34 is spaced from the outerwheels and secured in this spaced relation by means of sleeves 36 and37. vIt will be seen, therefore, that when the parts of the casing areseparated, the outer gears 33 and 35 may be quickly and easily removed,whereupon one ofthe sleeves may be removed and this permits removal ofthe intermediate gear 34. This construction also enables the device tobe manufactured at a comparatively slight cost, as it enables the gears33, 34 and 35 yto be outI from stock bars, 'while the sleeves 27 maybe'formed by cutting a cylindrical tube into short sections.V It isobvious that such construction is far less expensive than constructionsinvolving wheels having bosses and 'mustbe forged and cast and afterwardmachined to theproper shape andV dimensions.

Although two rods 9 are shown in Fig. 2, it is obvious that theinventionis not depended upon a number of such rods, and that the rod which isnotconnected with the shifter isonly a subsidiary securing element; l

Although I have described this embodiment of myinvention veryspecifically, it is not intended to limit this invention to these exactdetails of construction and arrangement of parts, but I am entitled toYmake changes within the scopeV of the inventive idea disclosed -in theforegoing description and 'following claims.

What I claim as my invention is: Y l Y 1. In a three-speed gearingmechanism, a

rotary driving. shaft, a larger gear wheelV mounted to rotate freely onthe driving shaft, a' smaller gear. wheelmounted to ro'- tate freely onthe driving shaft, a combined clutchV and gear member mounted 'to slidealongfsaidcdrivingshaft and being nonrotatable relative to the drivingshaft, a set of three gear wheels of different diameters mounted torotate in unison so that each one will actuate the other two, a'transmission membery connected to and rotatable by said larger gearwheel, and a shifter operatable to move said combined clutch and Vgearmemf 1 ber interchangeably into clutching engagement with said largergear Vwheel and smaller gear wheel and into mesh with one of the gearwheels of said set, the other two Agear wheels of said set being in meshwith the said larger and smaller gear wheels respectively.V

2. In a gearing mechanism, two casing different diameters, rigidlyconnected to'-v gether,.one of the wheels of said set being in mesh withthe gearrwheel of the said transmission device, and a shifter operatabley to move thek said combined clutch and gear member interchangeably intoclutchingengagement with the clutch member carried by the gearV of saidsleevev and into meshwith another one of the gear wheels of said set.

A3. In a gearing mechanism, two casing heads, a barrel having its endsclosedby said casing-heads and combining therewith to form a gear-case,a rotary shaftY ournaled in the gear case and having its middle 'part ofgreater diameterV than its end parts and thereby providing shoulders atransmission device comprising a sleeve4 and a gear wheel on the sleeveprovided with a clutch element, said transmission device having one sideagainst saidV casing and its.V opposite side against one of saidshoulders and being free on said shaft, a second gear wheel free on saidshaft, said second gear wheel having one side against said'casing anditsopposite side against the other one of said shoulders and providedwith a clutch element, a clutch member mounted on said shaft andslidable therealong for selective engagement with the clutch Velementsof the first and secondi first and second'said gear wheels,means to fshift said combined clutch and -gear inember` into i and'out o fengagement with' said transmission device and said second gear wheel,and aV securingmember engaged with said 'heads for uniting said barrelwith said heads vand coacting therewith to prevent axial movement ofsaid -shaft and'ofthef said transmission deviceV and transmission memberrelative *tol said casing.

4. In a gearing mechanism, a gear-case, a driving. shaft journaled in'the case and extending longitudinally thereof, a sleeve rotatablypositioned about the shaft and extending out of the gear-oase and havinga gear at its inner end provided with a clutch element7 a gear upon theopposite end portion of the driving shaft having a clutch element, aclutch gear slidably mounted upon the driving shaft and having clutchelements for engaging the Clutch elements of the first and secondmentioned gears When moved longitudinally of the driving shaft, a drivenshaft extending longitudinally of the gear-oase and having gears rigidlymounted thereon7 certain of the gears of the driven shaft being inengagement with the first and second mentioned gears of the drivingshaft and another gear carried by the driven shaft being engageable bythe sliding gear of the driving shaftV When the sliding gear is out ofengagement with the first andvseoondLmentioned gears, and means foradjusting the sliding gear upon the driving shaft.V

In testimony whereof I have hereunto set my hand.

XAVIER VB. DUNCAN.

